let's begin with abc's brian ross, with the latest right now. brian? >> good evening. there are important new clues into the bomb and the bomber. but the road begins with an examination of that bomb. important new details have emerged from fbi agents who say they have recovered a significant part, a mangled piece of one of the bombs, recovered on the scene. it turns out to be a common kitchen item. they say it is a medium-sized pressure cooker that was packed with explosives, wires, and an electronic circuit board, as well as tiny nails and ball bearings, in order to maximize the damage to anyone in the blast zone. authorities believe they can examine that particular half bomb now. they've got it at the base in virginia, where it's being examined by fbi technicians. they believe they can find signatures and footprints that would be unique to that bomb and perhaps match it up to other bombs somewhere else in the world, somewhere else in this country. that will be the road to finding the bomber. the fbi put out a plea to anyone who saw a person carrying an unusually heav